PC World Magazine just listed Windows Vista as #1 of The 15 Biggest Tech Disappointments of 2007 . I gleaned a list of how to disappoint customers from Dan Tynan's review.

"It's not that Vista is awful."
Lesson 1: Disappointment is achieved not by being utterly horrible, but by being just bad enough to disappoint. Just don't live up to expectations no matter how much you hype them.

"It's just that Vista isn't all that good."
Lesson 2: Disappointment is achieved by a lack of excellence and a lack of improvement over what came before. Encourage people to go back to what they were using before.

"When it debuted…imcompatibilities were rampant."
Lesson 3: Disappointment is achieved when you make your product hard to use and difficult to integrate into what they have and use. And along the way, make sure that those who would help you such as hardware and software makers stay unenthusiastic about working with you.

"The user account controls that were supposed to make users feel safer just made them feel irritated."
Lesson 4: Disappointment is achieved by ticking off your customers due to the frustrating experience of using your product. Make sure your customers are saying, "Why don't these guys get it right?" and "Why do I let them do this to me?"

"We couldn't help feeling more than a little gouged."
Lesson 5: Disappointment is achieved when you stick it to your customers, overcharging them for their disappointment. Like paying $299 for an upgrade that makes you want to go back to XP.

"...it will become increasingly hard to buy a new machine that doesn't have it pre-installed. And that's disappointing in its own right."
Lesson 6: Disappointment is achieved by not giving your customers a choice. Force your will on theirs. Box them in to your disappointing choice.

"And when the fastest Vista notebook PC World has ever tested is an Apple MacBook Pro, there's something deeply wrong with the universe."
Lesson 7: Disappointment is achieved when you keep reminding your customers that they really want a Mac.

So...how do your customers feel about your company?